Analysis of stepped wedge cluster randomized trials in the presence of a time-varying treatment effect.

ABSTRACT: Stepped wedge cluster randomized controlled trials are typically analyzed using models that assume the full effect of the treatment is achieved instantaneously. We provide an analytical framework for scenarios in which the treatment effect varies as a function of exposure time (time since the start of treatment) and define the "effect curve" as the magnitude of the treatment effect on the linear predictor scale as a function of exposure time. The "time-averaged treatment effect" (TATE) and "long-term treatment effect" (LTE) are summaries of this curve. We analytically derive the expectation of the estimator δ^$$ \hat{\delta} $$ resulting from a model that assumes an immediate treatment effect and show that it can be expressed as a weighted sum of the time-specific treatment effects corresp

SUBMITTER: Kenny A 

PROVIDER: S-EPMC9481733 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature